Suppose a nearby civilization was able to detect intelligent EM emissions from Earth (radio & TV, and I use the word "intelligent" loosely), and had an interest in responding. Those transmissions have only been going on for the last 100 years, so they most likely wouldn't even have received the oldest signals from Earth yet.

@Etmax: ...to move 2/3 of 10 billion people elsewhere will likely consume so much of our resources as to leave enough for much less than the 1/3 that is currently sustainable.

Unless we develop some amazing technology like the "Gates" in Robert Heinlein's "Tunnel in the Sky," there's no chance of reducing the population by exporting people to other planets.

The thing is that the human race is vunerable if all our eggs are in one basket (on one planet). After all of the folks (and other creature) who have lived and struggled and died for us to get where we are, it would be a shame to lose it all in a catastrophe -- it would be nice to know that the race wuld suvive -- and one wa yto increase the odds is to have colonys on other moons and planets and -- eventually solar systems...

@Max...I'd question your use of the word "other" in the above....makes more sense without it. Present company excepted, of course, but the human race as a whole does not display too many signs of intelligence........

@Bert I'm glad I'm not alone in understanding the magnitude of the problems. I've always enjoyed Star Trek and its progeny and love the knowledge that the various space programs have given us, but when you do the math you become aware what resources are needed to make all of these things come true it becomes quite a wake up call, and yes western countries (because they don't fight daily for survival) have ahd the time to work out what needs to be done but at the end of the day there is simply no global political will. Check this video out for some views on what we are up against:

If you get a chance, you should read Intelligent Life In The Universe by Carl Sagan & Russian astronomer I.S. Shklovskii. Written in 1966, long before Sagan was a celebrity, the material may seem a bit dated but is still fascinating. It covers a reasonably technical but readable discussion of cosmology, the evolution of stars and the elements of the periodic table within them, then proceeds in a step by step fashion, making very conservative judgements at each step, to make a calculated estimate of the number of advanced civilizations in our galaxy ("advanced" meaning substantially more advanced than our own) and concludes that the number -- just in our galaxy -- is between 50,000 and 1 million such civilizations, with an average separation distance of between a few hundred and about 1000 light years.

That's still an immense distance, not only for any conceivable physical visitation, but even for any meaningful electromagnetic communication -- unless of course the Star Trek warp field generator ever becomes possible :)

Seems to me that the "unsustainable" will become more evident as the populations of the "have-nots" start to approach the standard of living of the "haves." Just two countries today, China and India, account for 1/3 of the population of this planet. And both of them, but especially China, are going through big changes. So quite honestly, this is very much out of the control of the US and its closest allies, and all of our western "green" rhetoric. Attempting to lead by example is apparently very hard to do, eh?

Whatever the case may be, the closest star system appears to have no life-sustaining planets. According to the article, the closest solar system with life sustaining planets might be 12 light-years away. Still "close," in astronomic terms, even though it would take around 225,000 years to reach, with current technology. So, guys, we had better make this one planet work for us all.

In actual fact the greenest "modern" life to which everybody on earth should be entitled would need a planet with 2.5 to 3.5 times the resources that we currently.

It's extremely evident that we already have a situation where we have to accept that either 2/3 of the world population has to live well below the poverty line or the world population has to be reduced to a 1/3 of its current level.

While that is what is projected to happen over the next 150 years naturally, this isn't fast enough to prevent a global problem where we all suffer immeasurably. I fear we will be all at eachother's throats for a litre of water or a scrap of food long before enough of us have been moved "elsewhere"

The idea of expanding to other planets I think hides the fact that to move 2/3 of 10 billion people elsewhere will likely consume so much of our resources as to leave enough for much less than the 1/3 that is currently sustainable.